diff --git a/docs/configes sample/basic_config.json b/docs/configes sample/basic_config.json
index 9fb2c19..b26f7da 100644
--- a/docs/configes sample/basic_config.json	
+++ b/docs/configes sample/basic_config.json	
@@ -14,5 +14,8 @@
     },
     "basic_force" : {
         "name": ["x", "y", "x&y format:basic_number/unit1:[m]/unit2:[]"]
+    },
+    "basic_poi": {
+        "name": ["x", "y"]
     }
 }
\ No newline at end of file
diff --git a/libs/loads.py b/libs/loads.py
index be6b2d7..f4dbbf4 100644
--- a/libs/loads.py
+++ b/libs/loads.py
@@ -12,7 +12,7 @@ def config(file_name, stack=None):
         with open(file_name, "r") as jf:  # jf -> json file
             rd = json.load(jf)
     except FileNotFoundError:
-        raise
+        raise FileNotFoundError("no config file")
     if stack != None:
         rd = rd[stack]
     return rd